TOS Java SDK为Java开发者提供了访问火山引擎对象存储服务TOS（Tinder Object Storage）的系列接口。您可以通过Maven工具快速引入。本文档将给出TOS桶和对象的基本操作代码，供开发者参考，具体API文档请参考https://www.volcengine.com/docs/6349/79895
- Java 1.8或更高
- Maven
<dependency>
<groupId>com.volcengine</groupId>
<artifactId>ve-tos-java-sdk</artifactId>
<version>2.9.19</version>
</dependency>本节介绍，如何通过TOS Java SDK来完成常见的操作，如创建桶，上传、下载和删除对象等。
初始化TOSV2Client实例之后，才可以向TOS服务发送HTTP/HTTPS请求。 初始化客户端时，需要带上accesskey，secretkey，endpoint和region。初始化代码如下：
String region = "region to access";
String endpoint = "endpoint to access";
String accessKey = "your access key";
String secretKey = "your secret key";
TOSV2 client = new TOSV2ClientBuilder().build(region, endpoint, accessKey, secretKey);桶是TOS的全局唯一的命名空间，相当于数据的容器，用来储存对象数据。如下代码展示如何创建一个新桶：
String region = "region to access";
String endpoint = "endpoint to access";
String accessKey = "your access key";
String secretKey = "your secret key";
String bucket = "your bucket name";
TOSV2 client = new TOSV2ClientBuilder().build(region, endpoint, accessKey, secretKey);
CreateBucketV2Input input = new CreateBucketV2Input().setBucket(bucket);
try{
CreateBucketV2Output output = client.createBucket(input);
System.out.println("Created bucket location is " + output.getLocation());
} catch (TosException e) {
System.out.println("Create bucket failed");
e.printStackTrace();
}新建桶成功后，可以往桶中上传对象，如下展示如何上传一个对象到已创建的桶中：
String region = "region to access";
String endpoint = "endpoint to access";
String accessKey = "your access key";
String secretKey = "your secret key";
String bucket = "your bucket name";
TOSV2 client = new TOSV2ClientBuilder().build(region, endpoint, accessKey, secretKey);
String data = "1234567890abcdefghijklmnopqrstuvwxyz~!@#$%^&*()_+<>?,./ :'1234567890abcdefghijklmnopqrstuvwxyz~!@#$%^&*()_+<>?,./ :'";
InputStream stream = new ByteArrayInputStream(data.getBytes());
String key = "object-crud-"+System.currentTimeMillis();
try{
PutObjectBasicInput basicInput = new PutObjectBasicInput().setBucket(bucket).setKey(key);
PutObjectInput input = new PutObjectInput().setPutObjectBasicInput(basicInput).setContent(stream);
PutObjectOutput output = client.putObject(input);
System.out.println("Put object success, the object's etag is " + output.getEtag());
} catch (TosException e) {
System.out.println("Put object failed");
e.printStackTrace();
}如下展示如何从桶中下载一个已经存在的对象到本地文件：
String region = "region to access";
String endpoint = "endpoint to access";
String accessKey = "your access key";
String secretKey = "your secret key";
String bucket = "your bucket name";
String key = "your key name";
String filePath = "your local file name to store downloaded file"; // eg. "/home/user/aaa.txt"
TOSV2 client = new TOSV2ClientBuilder().build(region, endpoint, accessKey, secretKey);
GetObjectV2Input input = new GetObjectV2Input().setBucket(bucket).setKey(key);
try (GetObjectV2Output object = client.getObject(input);
FileOutputStream writer = new FileOutputStream(filePath)) {
if (object.getContent() != null) {
int once, total = 0;
byte[] buffer = new byte[4096];
InputStream inputStream = object.getContent();
while ((once = inputStream.read(buffer)) > 0) {
total += once;
writer.write(buffer, 0, once);
}
System.out.println("object's size is " + total + " bytes");
} else {
// key不存在返回null
System.out.println("key " + key + " not found");
}
} catch (TosException | IOException e) {
System.out.println("getObject error");
e.printStackTrace();
}如下展示如何从桶中删除一个已经存在的对象：
String region = "region to access";
String endpoint = "endpoint to access";
String accessKey = "your access key";
String secretKey = "your secret key";
String bucket = "your bucket name";
String key = "your key name";
TOSV2 client = new TOSV2ClientBuilder().build(region, endpoint, accessKey, secretKey);
DeleteObjectInput input = new DeleteObjectInput().setBucket(bucket).setKey(key);
try {
DeleteObjectOutput output = client.deleteObject(input);
System.out.println("Delete success, " + output);
} catch (TosException e) {
System.out.println("Delete failed");
e.printStackTrace();
}